This invention relates in general to a new and improved orthodontic bracket to be used in conjunction with other brackets on centrals, laterals, cuspids and bicuspids for uprighting teeth without the need for mounting uprighting springs, and more particularly for an improved bracket having means for allowing crown tipping, root uprighting, and torquing functions and which includes means for producing the final uprighting function without the use of individual uprighting springs.
Heretofore it has been known to provide orthodontic brackets having means for accommodating crown tipping functions, root uprighting functions, and torquing functions, as disclosed in U.S. Pat. Nos. 4,877,398 (""398) and 5,125,832 (""832). Such a bracket is made and sold by TP Orthodontics, Inc. of Westville, Ind. (TP), under the registered trademark TIP-EDGE, owned by TP Orthodontics, Inc. While these brackets may receive round or rectangular wire, they are designed to perform torquing functions with rectangular wire, and it is preferred that rectangular wire be used in the later stages of treatment.
Further, the brackets above referred to include vertically extending slots or openings for receiving the tails of uprighting springs to perform a root uprighting function. It should be appreciated that it is well known that the vertically extending openings may also receive the tail of a rotating spring for performing a rotating function or a pin for hooking a ligature. U.S. Pat. No. 4,842,514 discloses a type of uprighting spring that may be used with brackets having vertical openings.
It has also been known to provide an orthodontic bracket having a pair of contiguous labiobuccally opening archwire slots, one of which allows tipping and uprighting movements and the other of which provides torquing movement, as disclosed in U.S. Pat. No. 4,842,512. It has also been known to provide a bracket having a pair of contiguous archwire slots, one of which allows crown tipping, limits root uprighting, and controls torquing, while the other slot functions to stabilize tooth movement in three dimensions, as sold by TP Orthodontics, Inc. of Westville, Ind., and illustrated in TP""s 1998 Product Catalog.
The improved orthodontic bracket of the present invention overcomes the need to use uprighting springs for final finishing with a system using brackets having an archwire slot like the brackets in the above ""398 and ""832 patents to apply root uprighting and/or tipping forces and torquing forces to teeth, as well as the need for selectively mounting such springs to apply such root uprighting and/or tipping forces by additionally incorporating a generally horizontal uprighting lumen or tunnel/opening for receiving an uprighting wire. As to the archwire slot in the bracket of the present invention that allows crown tipping, the ""398 and ""832 patents are incorporated by reference. Further, the bracket of the present invention reduces the need for individual uprighting springs and therefore also the possibility of improperly mounting such springs during the course of treatment.
The improved orthodontic bracket of the present invention, while having a horizontally opening archwire slot formed to permit mesial-distal crown tipping and to limit root uprighting, includes an additional mesiodistally extending generally horizontally directed tunnel, opening or lumen for receiving a relatively small, super-elastic archwire or a high-tensile uprighting wire that is threaded through similar horizontal openings in adjacent brackets. The horizontal tunnels, tubes, or lumens do not connect into the main archwire slots of the brackets. The tunnels extend generally parallel to the occlusal of the arch on which the brackets are mounted. So, when the patient enters the final stage of treatment and all of the extraction spaces, if any, are closed, the crowns of the teeth may be tipped mesially or distally and in some cases also labially or lingually by threading an uprighting wire through the tubes, wherein the energy of the wire uprights the brackets/teeth.
While the preferred means of attaching the uprighting wire to the bracket is the insertion into a tunnel or lumen, it must be realized that the uprighting wire could be inserted into an open horizontally facing slot. This uprighting slot or lumen could be located in the face of the bracket either gingival or occlusal to the archwire slot.
The slot or lumen could be horizontal wit the occlusal plane so that the uprighting wire would become passive and its forces drop to zero when all the teeth have been uprighted. The slot or lumen could also be angled relative to the horizontal axis of the archwire slot to facilitate engagement of the uprighting wire when the tooth is tipped or to insure a greater initial force, or a continued force after the tooth has been uprighted to the tip and/or torque limits programmed into the horizontal stops within the archwire slot.
The advantage of an open uprighting slot on the labial face of the bracket over a lumen would be in the ease of insertion. Some disadvantages would be the need for retention via a self-locking feature or the use of a ligature, lack of positive engagement and inferior rotational control.
Also, when the uprighting wire is located above or below the plane of the main archwire, whether in a tunnel or a slot, it could interfere with desired changes in the labial-lingual inclination or torquing of the teeth.
The relatively small, super-elastic or high-tensile uprighting wire traveling through the uprighting slots or tunnels are generally substantially continuous, but may be segmented, and may extend from one end of the dental arch to the other end or a section thereof. Thus, the small and continuous or segmented wire can be threaded through the tunnels in the brackets, as well as the tubes of the molars if indicated, in the final stage. Subsequently, the main archwire is placed in the horizontally opening archwire slots, and retained in the slots with suitable ligatures such as elastomeric rings, or a removable cap as used with self-ligating brackets.
An uprighting tunnel, opening or lumen may be continuous or segmented, and may be formed by a plurality of segmental members. Further, a tunnel may be angled in relation to the occlusal plane or have at one end a plurality of paths for selective use depending on the degree of tipping or uprighting required.
Barring any damage to the system, the patient then need not return for a subsequent visit for approximately two to three months, after which time depending upon the initial degree of tipping of the teeth, the roots may be properly uprighted. If further uprighting is required, a larger size wire or higher tensile wire can be threaded through the tunnels or placed in the uprighting slots in the faces of the brackets to complete uprighting. Once the desired uprighting has been accomplished, the appliances may then be removed for the subsequent placement of suitable retainers.
The use of a super-elastic or high-tensile wire in the openings results in the elimination of the need for uprighting springs, and produces greater comfort in the mouth of the patient. The hygienic conditions of the mouth are improved by the absence of the springs which can harbor food particles. Further, the elimination of uprighting springs enhances the aesthetics of the system, and prevents the possibility of selecting an incorrect uprighting spring resulting in applying a force in the wrong direction.
It is therefore an object of the present invention to provide a new and improved orthodontic bracket that eliminates the need for uprighting springs in the final stage of patient treatment, and that additionally makes it impossible to apply undesired uprighting forces that could be applied by inserting the incorrect uprighting spring.
A further object of the present invention is in the provision of an improved orthodontic bracket having a horizontally extending continuous or segmented tunnel, tube, or slot through which a relatively small, super-elastic or high-tensile uprighting wire may be threaded for applying root uprighting forces to teeth, thereby eliminating the necessity to use uprighting springs, and which improves mouth hygiene, reduces patient visits, and improves patient comfort.
Another object of the present invention is to provide a new and improved orthodontic appliance having either an uprighting lumen disposed lingually of an archwire slot that controls tipping, uprighting and torquing, or an uprighting lumen or slot disposed above or below the archwire slot.
Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts.